1. Field of the Invention
The present invention relates to a granular composition for a ruminant containing choline or a physiologically acceptable derivative thereof having a high deliquescent property. More specifically, it relates to a granular composition for a ruminant in which choline or a physiologically acceptable derivative thereof usually fed with, for example, an animal feed, is protected from, for example, the action of microorganisms and a rumen solution present in a rumen of a ruminant and from the ruminating action and is digested and absorbed in an abomasum and downstream thereof.
2. Description of the Related Art
Choline and the physiologically acceptable derivatives thereof (i.e., sometimes referred to as "cholines" hereinbelow) are remarkably deliquescent, and, since they become liquid by absorbing humidity moisture when simply allowed to stand in atmospheric conditions, even the granulation thereof is quite difficult in the art. Accordingly, at present, liquid cholines and cholines adsorbed on powdered carriers (e.g., 50% choline adsorbed on cone cob meal) are produced, other than crystalline cholines. These cholines are used as a feed additive for monogastric animals, but are not used for ruminants such as cattles and sheep because they decompose in the rumen thereof, whereby they are not effectively utilized in an abomasum and an unpreferably large amount of the cholines is required.
As is known in the art, when physiologically active substances are directly orally fed to ruminants, most of those substances are decomposed by a variety of organisms present in the rumen thereof or a rumen solution and the physiological activities thereof are lost, and therefore, these physiologically active substances cannot be effectively utilized.
Thus, a so-called rumen-bypass granular agent, i.e., an agent which is not solubilized or decomposed in the rumen and is dissolved and absorbed in the abomasum and downstream thereof, is important to an effective utilization of physiologically active substances in ruminants, and various such granular agents have been developed.
For example, JP-B(Kokoku)-48-12785 (i.e., U.S. Pat. No. 3541204) proposes a controlled release granular composition for feeding to ruminants by coating the granular agent with a continuous film of one or more protective substances. Various protective substances are also discloses in JP-B-56-1057, JP-B-59-105780, and JP-A(Kokai)-58-175449.
Furthermore, JP-A-60-141242 proposes a granular agent obtained by covering physiologically active substances with a C.sub.14 -C.sub.22 fatty acid, followed by a coating thereof with the above-mentioned protective substances.
The above-mentioned proposals can be practically applied to physiologically active substances having a relatively small solubility such as methionine and tryptophan and at most glucose. However, when these proposals are applied to cholines, the resultant granules are dissolved or decomposed in a ruminant because only cholines have the specifical solubility and deliquescent property, and furthermore, the granulation per se is difficult.